The present invention relates to a polycarbonate resin composition, and more particularly, to a polycarbonate resin composition which is quite excellent in solvent resistance and further which is excellent in stiffness, impact resistance, and properties such as moldability and appearance. This polycarbonate resin composition is useful as a material for use in production of industrial articles such as a car bumper and home electric articles.
A polycarbonate resin is known as a molding resin having excellent physical properties (e.g., stiffness) and thermal properties. A molded article of the polycarbonate resin or polycarbonate resin molding has a disadvantage in that cracks are readily formed in the molding upon application of concentrated stress in a certain kind of solvent. Another disadvantage of the polycarbonate resin as encountered during the molding process is that molding temperature and pressure are high as compared with other resins since its melt viscosity is high.
In order to overcome the above problems of the polycarbonate resin, that is, to improve poor solvent resistance and moldability without reducing its inherent excellent physical properties, it has been proposed to compound various polyesters to the polycarbonate resin.
For example, a composition comprising a polycarbonate resin and polyalkylene terephthalate derived by copolymerization of a bifunctional carboxylic acid component and a diol component having a large amount of an aromatic ring is disclosed in Japanese Patent Publication Nos. 16137/1982, 37633/1979, and Japanese Patent Application Laid-Open No. 102648/1975. This composition, however, has disadvantages in that burning is formed during the molding process because the aromatic ring content of the diol component is increased and in that the diol component is expensive, which is disadvangeous from an economic standpoint. In addition, a composition comprising a polycarbonate resin and polyalkylene terephthalate containing cyclohexanedimethanol as the diol component is disclosed in Japanese Patent Application Laid-Open No. 94536/1978. Addition of this polyalkylene terephthalate, however, seriously decreases stiffness and fails to improve solvent resistance sufficiently. Moreover the composition has a disadvantage in that it is colored and thus can be used only in limited applications.